The Strangest VBA Question I Have Ever Seen (VBASigned Possible Boolean Error)

Question

In MS Word, I added code to see if the document was missing its digital signature, or at least I thought I did. I decided to share before testing this on other systems.

Sub test()
    If Not ThisDocument.VBASigned Then
        Debug.Print "I am NOT signed"
    End If
End Sub

Problem: The code above gives the same result regardless of whether the document is digitally signed. If I change the code by deleting Not, I still get unexpected results.

I tried to force things by doing things like:

If Not CBool(ThisDocument.VBASigned) Then

But more surprisingly, the following code also fails:

Sub test()
    Dim isSigned As Boolean
    isSigned = ThisDocument.VBASigned

    If Not isSigned Then
        Debug.Print "I am NOT signed"
    End If
End Sub

Even if ThisDocument.VBASignedANDs isSignedare TRUE...
but if changed isSigned = ThisDocument.VBASignedto isSigned = True, then everything will work as expected.

- ? ?

---

:

• , Option Explicit, Debug.
  :

  Option Explicit
  
  Sub test()
      Dim isSigned As Boolean
      isSigned = ThisDocument.VBASigned
      Debug.Print ThisDocument.VBASigned
      If Not isSigned Then
          Debug.Print "I am NOT signed"
      End If
  End Sub
  

  :

  True
    

• : True * 0 - 1.

  Sub test()
      Dim isSigned As Boolean
      isSigned = ThisDocument.VBASigned
      Debug.Print ThisDocument.VBASigned
      If Not (isSigned * 0 - 1) Then
          Debug.Print "I am NOT signed"
      End If
  End Sub
  

  () :

  True

Answer 1

, SlowLearner, , Word VBASigned 1, .

If, Not 1 -2, Not 0 -1 - , Not VBASigned (.. -False) .

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MSDN , VBASigned , ( TypeName(ThisDocument.VBASigned)) Boolean, , , .

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, CBool(ThisDocument.VBASigned) * 1 1, a CBool(1) * 1 -1. , , , VBA , Boolean (, ThisDocument.VBASigned ), . , CBool Boolean, -1.

---

, :

Sub test()
    Dim myVBASigned As Integer
    Dim isSigned As Boolean
    myVBASigned = ThisDocument.VBASigned 'Store as Integer
    isSigned = myVBASigned               'Convert to a "true" Boolean

    If Not isSigned Then                 'Use the "true" Boolean
        Debug.Print "I am NOT signed"
    End If

End Sub

Answer 2

Excel , Word.

, VBA VBA:

Excel:

Sub testExcel()
    Dim isSigned As Boolean
    isSigned = ThisWorkbook.VBASigned
    Debug.Print ThisWorkbook.VBASigned
    If Not isSigned Then
        Debug.Print "I am NOT signed"
    Else
        Debug.Print "I AM signed"
    End If
End Sub

True

Word

Sub testWord()
    Dim isSigned As Boolean
    isSigned = ThisDocument.VBASigned
    Debug.Print ThisDocument.VBASigned
    If Not isSigned Then
        Debug.Print "I am NOT signed"
    Else
        Debug.Print "I AM signed"
    End If
End Sub

True

, Word .

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• Windows 10 x64
• Office Professional Plus 2016
  • 1703 Build 7967.2139
  • 64-